Mort Lindsey, a conductor and bandleader who helped revitalize the sputtering career of singer Judy Garland through a series of popular concerts and later served as the musical director for “The Merv Griffin Show,” died May 4 at his home in Malibu, Calif. He was 89.

He had complications from a broken hip, said his son Steve Lindsey.

In a six-decade musical career, Mr. Lindsey arranged songs and directed performances for many of the industry’s brightest stars, including Frank Sinatra, Dean Martin, Barbra Streisand, Elton John and Garland’s daughter Liza Minnelli. (With Johnny Mercer, Mr. Lindsey wrote the song “Lorna,” about Garland’s other daughter, Lorna Luft.)

Perhaps his greatest triumph was conducting Garland’s April 23, 1961, performance at New York’s Carnegie Hall. A live recording of the concert won four Grammy Awards, including album of the year, and spent three months at No. 1 on the Billboard top 200.

Mr. Lindsey began his career in the late 1940s as a studio pianist for NBC in New York and later became the staff conductor for Pat Boone’s ABC variety show.

Orchestra leader, arranger, composer, and musical director Mort Lindsey. (REUTERS)

His collaboration with Garland began in the early 1960s. At the time, the singer was recovering from alcohol and drug abuse. Two Hollywood agents, Freddie Fields and David Begelman, organized a cross-country concert series to rejuvenate Garland’s moribund career.

Through Begelman, Mr. Lindsey was tapped to prepare an orchestra to accompany Garland during a concert at the Concord Hotel in Kiamesha Lake, N.Y.

At a recording studio, Mr. Lindsey was whipping “the orchestra into shape,” he told Larry King on CNN in 2001, when Garland walked in wearing a fur coat. “And she listened, and she started to smile.”

Mr. Lindsey said Garland demanded to Begelman that the conductor join them on the tour. Aware of Garland’s past struggles, Mr. Lindsey at first refused. But Begelman insisted.

“So I gave him some impossible terms,” Mr. Lindsey said in 2001. “And he met them. And we went to the Concord.”

The tour’s climax was the Car­negie Hall concert, Garland’s debut on the famous stage. An audience of 3,000 — including Richard Burton, Julie Andrews and Lauren Bacall — came out for the performance. Mr. Lindsey arranged the show’s rousing overture, a snazzy medley of Garland’s hits, including “The Trolley Song,” “Over the Rainbow” and “The Man That Got Away.”

Garland’s throaty renditions of “Puttin’ on the Ritz,” “I Can’t Give You Anything But Love” and “San Francisco” earned repeated standing ovations, whistles and cheers.

“All you have to do is talk to people who went to that concert, and they will tell you it was the greatest night in show business,” Mr. Lindsey told the Record of Bergen County, N.J., in 1998. “It was like a revival meeting.”

From 1962 to 1986, Mr. Lindsey served as musical director and conductor for Merv Griffin’s variety show. In a 1971 New York Times review of a two-night musical special, critic Jack Gould wrote that Mr. Lindsey was “the hero” of Griffin’s program.

“With amazing accuracy and musicianship,” Gould wrote, Mr. Lindsey “led his band through all the different styles and arrangements associated with the guests of honor. To shift effortlessly from the champagne horn of Lawrence Welk to the Dixieland beat of Bob Crosby left no doubt of Mr. Lindsey’s versatility.”

Mr. Lindsey won an Emmy Award for his performance alongside Streisand in the 1968 concert film “A Happening in Central Park” and collaborated with Minnelli on the 1972 television special “Liza With a Z.”

Of all the singers he knew, Mr. Lindsey said, the most invigorating was Garland.

“Everytime she sang, I got goose bumps,” Mr. Lindesy told Larry King. “My back was to her, too.”

Morton Lippman was born March 21, 1923, in Newark. Once in show business, he changed his name to Mort Lindsey. He received a bachelor’s degree in 1944, a master’s degree in 1948 and a doctorate in musical education in 1974, all from Columbia University.

Survivors include his wife of 57 years, Judy Lindsey, of Malibu; two sons and a daughter from his second marriage; and a son and two daughters from a previous marriage, which ended in divorce.

At the Carnegie Hall show, Mr. Lindsey once recalled, Garland took her time getting to the stage, despite its importance for resuscitating her career.

“Judy knew how to milk an audience,” Mr. Lindsey told Vanity Fair in 2011. “I see her standing in the wings. She’s not doing anything, just looking across the stage. She’s looking at me, and I’m looking at her. . . . There’s Ethel Merman and Rock Hudson and Benny Goodman, all these big shots sitting down in the first row. . . . But she knows what she’s doing. Finally she gives me a nod, and I start the overture.”